In the transportation sector there is an increasing trend to reduce the weight of vehicles. This trend is for example leading to the use of double-sided structural adhesive tapes including tapes with a single structural adhesive layer (so-called transfer tapes) where they have previously not been used or to the application of tapes in new configurations that are more demanding and result, for example, in higher stress-strain forces to which the adhesive tape may be subjected. Double-sided adhesive tapes have a first and second major adhesive surface, respectively. They also have a first and second minor side extending perpendicular to the first and second major surface. Between each of the surfaces an edge forms the transition from one surface to the other.
Structural adhesives comprise cross-linkable but not yet cross-linked adhesive which may suffer from the so-called cold flow effect, i.e. the adhesive creeps on a surface it is attached thereby deteriorating its original shape and oozing. This effect is particularly pronounced when an adhesive tape having at least one adhesive layer comprising a structural adhesive is wound into a roll.
U.S. Pat. No. 4,415,615 discloses adhesives tapes used to bond two substrates together to form a bonded composite. Such adhesive tapes are used, for example, in the automotive industry where they may be employed to bond various components to the body of a car or other motor vehicles. Typically they are used to bond such parts as emblems, plastic parts as well as rubber gaskets to doors.
Patent application WO 98/23488 discloses an elongate mass of cold-flowable material and a liner in which the liner is wrapped around the material with the liner inside surface facing the peripheral surface of the material with first and second regions of the liner extending away from the material. The cold-flowable material comprises a hot-melt pressure sensitive adhesive and the liner is a polyethylene liner that also comprises silicone.
Patent application WO 98/23488 discloses a method of enclosing a mass of cold-flowable material with a liner. The method comprises the steps of: contacting a central region of an inside surface of an elongate liner with portion of the outer peripheral surface of an elongate mass of material, bringing the first and second regions of the liner together to enclosed the mass of material with the liner and arranging the wrapped material on the core.
Patent application EP 2,529,856 discloses a method of joining two metal panels with an adhesive sheet which comprises a thermosettable composition. The method comprises the steps of: providing an adhesive sheet material near an end of the metal panels and adhering the metal panels together such that the adhesive sheet is between the metal panels thereby forming a metal joint and heating the metal joint.
It is desirable to provide a roll of an adhesive tape comprising at least one layer of a structural adhesive suitable for use in the automotive market that exhibit less cold flow than such rolls disclosed in the art and preferably essentially no cold flow.